Heavy burden plate feeder suspension



July 16, 1963 L. c. ERICKSON 3,097,738

HEAVY BURDEN PLATE FEEDER SUSPENSION Original Filed March'28, 1958 s Sheets-Sheet 1 L I J- Zjj 50111? July 16, 1963 c. ERICKSON HEAVY BURDEN PLATE FEEDER SUSPENSION Original Filed March 28, 1958 s Sheets-Sheet 2 //vV5/V70R 132mm Cind sow July 16, 1963 L. c. ERICKSON HEAVY BURDEN PLATE FEEDER SUSPENSION Original Filed March 28, 1958 United States Patent HEAVY BURDEN PLATE FEEDER SUSPENSION Lewis C. Erickson, Duluth, Minn, assignor to National iron Company, Duluth, Minn., a corporation of Delaware Original application Mar. 28, 1958, Ser. No. 724,567. Divided and this application Aug. 1, 1960, Ser. No. 46,725

1 Claim. (Cl. 198-220) This invention relates to reciprocating plate feeders. More particularly, it relates to a novel means for supporting the plate of such a feeder while it reciprocates in effecting the feeding action.

This application is a division on my presently pending application Serial Number 724,567 filed by me March 28, 195 8, and entitled Reciprocating Platte Feeder.

"Reciprocating plate feeders as heretofore known have had many disadvantages, some of which were of such magnitude that they were completely unsatisfactory for certain purposes. Such feeders conventionally have a plate or feeder deck mounted across the discharge of a hopper for reciprocating movement whereby the material discharged from the hopper will be fed uniformly onto a conveyor or into a truck or other receptacle. In such reciprocating plate feeders the reciprocating plate supports the material to be discharged from the hopper and effects the uniform feeding action by moving away from the discharge or laterally of the hopper a certain distance during one part of its reciprocating movement whereupon the material in the hopper will slide down behind the material formerly supported at the mouth or discharge of the hopper by the reciprocating plate. Thus when the reciprocating plate moves in the opposite direction back toward the hopper, the material at the outer end of the reciprocating plate is forced off the end of the plate as the latter is drawn back toward the hopper. In this manner, the material may be fed uniformly through the reciprocating action of the plate feeder which serves as a movable bottom for the hopper.

In reciprocating plate feeders, as heretofore known it has been conventional to support the reciprocating plate with rollers which are of relatively small diameter and are mounted for rotation about axles. 'Ihe rollers ride on rails or tracks supported on the feeder or on the supporting frame for the feeder. Such a construction has numerous disadvantages which make them undesirable for use in reciprocating plate feeders and are entirely unsatisfactory for use in situations where the loads are heavy and the shocks are severe. A primary disadvantage in utilizing rollers is that they tend to wear rapidly because dirt accumulates on the rail or track and enters the bearings for the axles of the rollers and because there is a frictional wear caused by the dirt on the rail and relative slipping movement between the weight-bearing surfaces. Rollers have a distinct disadvantage in addition to their rapid weaning in that they must be lubricated frequently ice possible. It is diflicult also to adjust the height or angle of inclination of the feeder deck when the plate is supported by rollers.

It has also been conventional in plate deck feeders to cause the plate to reciprocate through the use of eccentrics. An eccentric drive however, is impractical for situations requiring high torque such as is the case where the feeder deck is subjected to heavy loadings and moved at slow speeds. In such situations, the power requirements are extremely high if eccentrics are used and in some more extreme situations, the plate deck feeder cannot be driven by an eccentric of practical proportions.

and must be frequently replaced and require constant maintenance. In addition, the rollers tend to stick and therefore cause substantial problems and loss of time and production. The small diameter rollers are unsatisfactory for heavy loading and jarring such as are present when heavy rocks or ore are deposited upon the feeder deck of such a construction. In such instances, the rocks often weigh several hundred pounds and sometimes even over one or two tons, and will drop a number of feet onto the plate feeder. This subjects the plate feeder to very severe abuse and it has been found that rollers are entirely unsatisfactory for this purpose. Rollers therefore, are practical for use only in situations where the loads and capacities are small. In addition, rollers require housings to prevent the entrance of dust and dirt insofar as is In instances of heavy loading, the plate deck feeder would require an extremely large eccentric which in turn would require large bushings so that the entire construction would be prohibitively expensive. My invention is designed to overcome each of the above difiiculties.

My invention, three forms of which are disclosed herein, eliminate the above disadvantages by eliminating the use of rollers such as described above. -I eliminate the use of rollers by substituting therefore support means which utilize rocker surfaces to prevent the wear attendant between weight-bearing surfaces of this means. As a result instead of high friction and consequent rapid wearing and all of its attendant disadvantages, my support means has substantially eliminated these problems and provided a relatively trouble-free uniform feeding device.

It is a general object of my invention to provide a novel and improved reciprocating plate feeder of simple and lnexpensive construction and operation.

A more specific object is to provide a novel and im proved reciprocating plate feeder which will operate in a more efficient and trouble-free manner and yet can be manufactured and serviced more inexpensively than similar plate feeders as heretofore known.

Another object is to provide a novel and improved reciprocating plate feeder which is capable of eflicient and trouble-free operation at heavy load capacities with a minimum of servicing and expense.

Another object is to provide a novel feeder of the type described which is constructed so as to be self cleaning and require little if any lubrication.

Another object is to provide a novel and improved reciprocating plate feeder which can be operated at heavy load capacity for prolonged periods with little if any wear, servicing or maintenance.

Another object is to provide an improved reciprocating plate feeder which can be operated at heavy load capacities with a minimum of power requirements.

Another object is to provide a novel reciprocating plate feeder which can be operated at all load capacities with much less wear, maintenance, lubrication and expense than possible with reciprocating plate feeders as heretofore known.

Another object is to provide a novel and improved reciprocating plate feeder the parts of which need not be protected from dirt and which will function in a more satisfactory manner than those of reciprocating plate feeders as heretofore known.

These and other objects and advantages of my invention will more fully appear from the following description made in connection with the accompanying drawings wherein like reference characters refer to similar parts throughout the several views and in which:

'FIG. 1 is a perspective view of one form of my invention;

FIG. 2 is a side elevational view of the same;

FIG. 3 is a front end elevational view of the same;

FIG. 4 is an elevational view on an enlarged scale of the anchoring means for the cables by means of which 3 the latter is attached to the reciprocating plate feeder or feeder deck;

FIG. 5 is a side elevational view of a second embodiment of my invention with the supports for the feeder shown in section;

FIG. 6 is a vertical sectional view taken along line 6-6 of FIG. 5.

FIG. 7 is a vertical sectional view of one of the rockers and cradles by means of which the supporting rods support the reciprocating feeder deck;

FIG. 8 is a side elevational view of a third embodiment of my invention with the adjacent side walls removed and with portions thereof broken away to better illustrate the construction;

FIG. 9 is a vertical sectional view taken along line 99 of FIG. 8;

FIG. 10 is a perspective view on an enlarged scale of one of the rockers by means of which the feeder deck is supported; and

FIG. 11 is a perspective view on an enlarged scale of the keeper which prevents the rockers from creeping longitudinally of the feeder deck.

The first and simplest form of my invention is best illustrated in FIGS. 1-4 wherein there is shown a reciproeating plate feeder which is particularly well adapted for handling relatively small loads and capacities. As shown, this reciprocating plate feeder includes a frame 15 which supports a hopper 16 and also supports a motor M which drives by Ia belt 17, a gear reducer indicated generally as 18. This gear reducer 18 has a crank arm 19 which constitutes the output shaft thereof. This crank arm 19 is pivotally connected by a heavy bearing 20a to a rod 20 which in turn is pivotally connected to the rear portion of the reciprocating feeder deck 21. As best shown in FIGS. 1-2 this rod 20* is pivotally connected to one of the cross supports 22 and 23. As shown, the reciprocating plate or feeder deck 21 is supported at each of its sides by a pair of cables indicated by the numeral 24. Each of the cables 24 is looped at its lower end as best shown in FIG. 4 and anchored to an anchor bracket 25 by means of a clamping plate 26 and a pair of bolts 27 which pass through the bracket 25. The bracket 25 is adjustably mounted upon one of the cross supports 22 or 23 as the case may be and held in place as by a bolt 28 which extends through a vertically elongated slot 29 formed in the cross supports. An adjustment bolt 30 extends downwardly from the leg of the U-shaped cross support as best shown in FIG. 4 to permit the feeder deck 21 to be adjusted vertically and to have its angle of inclination altered as desired.

The upper ends of each of the cables 24 are secured to the frame 15 by means of a rocker 31 and a clamping plate 32 and a pair of bolts 33. As best shown in FIG. 2, the rocker plate 31 has a depending portion 31a which has a curved weight supporting surface 31b about which the upper end portion of the cables 24 may rock. The portion of the cable 24 which bears against the curved rocking surface 31b is the other weight-bearing surface which cooperates with the curved surface 31b to support the weight of the reciprocating plate 21 as it is moved forwardly and backwardly by the rod 20 It will be noted that the curved rocking surface 31b has a relatively large radius and that there is no relative slipping movement between the cooperating weight-bearing surfaces of the rocker 3 1 and the cable 24. On the contrary, there is a mere relative rocking motion between these two surfaces which substantially eliminates frictional wear therebetween during the reciprocating movement of the plate or panel 21. The curvature of surface 31b insures that cables 24 will not bend at one point only and break because of fatigue at that point the large radius of curvature of surface 31b insures that the cable will flex within its normal bending capabilities.

It will be noted that the feeder deck 21 extends across the discharge 16w of the hopper 16 and extends laterally of the hopper so as to receive thereon the material discharged through the hopper and to control the flow of material therethrough. If the feeder deck 21 is allowed to remain motionless the material will cease to flow through the discharge 16a of the hopper while if it is reciprocating, it will cause the material to be fed uniformly off the outer end of the feed deck. FIG. 2 shows that the feeder deck extends laterally of the hopper and is in a position to receive the material therefrom.

In FIG. 2 the reciprocating plate feeder is shown in position to withdraw the material from the hopper 16 and deposit it at a uniform rate upon a conveyor indicated generally as 34. This particular embodiment of my invention completely eliminates the problems heretofore experienced in the use of rollers to support the reciprocating feeder deck as outlined hereinbefore. This particular construction requires a minimum of maintenance and care. It will be noted that the support for the feeder deck 21 does not involve use of rollers and therefore there is no need to replace the same when they become worn. Very little if any lubrication is required in this type of construction and the rocking surfaces 31b tend to clean themselves in that any dirt or foreign material which may fall between the curved surface 31b and the cable 24 will be crushed and will immediately free itself by falling out of that area. It will be noted also that it is a relatively easy matter to change the height of the feeder deck or to change its angle of inclination when desired. It will also be noted that the construction of this type of support for the reciprocating plate feeder is extremely inexpensive and simple to manufacture and operate.

The second embodiment of my invention is particularly well adapted for use in situations of heavy loading and capacities. For example, in the movement of iron ore and the like, extremely heavy loads must be conveyed and uniformly deposited upon conveyors or into trucks or other receptacles. In the movement of such relatively heavy materials it is common for the material to drop at least several feet and in view of the fact that the individual chunks may weigh several hundred pounds, the equipment which must handle this material must be able to withstand heavy jarring and unusually heavy loads. The embodiment shown in FIGS. 5-7 inclusive, can handle extremely heavy loads and capacities without excessive and prohibitive maintenance and replacement requirements. The embodiment shown includes a supporting frame indicated generally as 35 which supports a hopper 36 having a discharge opening 36a across which a reciprocating feeder deck 37 is mounted. This feeder deck 37 is supported by a plurality of transversely extending cross supports such as 38 and is caused to reciprocate by means of a differential type cylinder indicated generally as 39. As best shown in FIG. 5, the piston 39a has opposed ends the area of one of which, as shown is substantially twice the area of the other. The end of the piston 39a which has the smaller area is continuously connected to the pump as shown and the end of the piston having the larger area is alternately connected to the pump and to the reservoir by a valve 3%. When the valve 3% connects the cylinder to the reservoir it cuts off the flow from the pump to the end of the piston having the larger area and when this valve is opened to permit the fluid to flow from the pump to the end of the piston having the larger area, the valve cuts off any flow into the reservoir. By controlling the valve the feeder deck 37 may be caused to reciprocate forwardly and backwardly with a minimum of power requirements. As the feeder deck 37 moves forwardly, the material contained within the hopper 36 slides downwardly along the inclined walls 36a and behind the material on the forward end of the feeder deck 37. When the feeder deck 37 is retracted by the cylinder 39', the material at the outer end of the feeder deck is caused to slide off the outer end and drop into the truck indicated by the numeral 40.

The feeder deck 37 is suspended in a slightly different manner in the embodiment shown in FIGS. 5-7, inclusive, but the same principle is utilized. The feeder deck 37 is supported at each side by a pair of supporting links or rods 41. Each of these rods 41 is supported on the hopper 36 at its upper. end in the manner shown. A bracket 42 is mounted upon the hopper 36 and supports a cradle member 43 which in turn supports a rocker member 44 through which the rod 41 passes. A nut 45 prevents the rod 41 from being drawn downwardly through the rocker member 44. The cradle 43 and the bracket 42. are each provided with elongated openings to permit the rods 41 to swing forwardly and backwardly with the feeder deck 37 which it supports.

,The lower end of each of the rear supporting rods 41 is secured to the feeder deck 37 in such a manner as to permit the feeder deck to reciprocate forwardly and backwardly while being supported by these rods. Each of the rods 41 extends downwardly through a cradle member 46 which is mounted upon a pair of the cross supports 38 and carries a rocker 47, a plurality of Belleville springs 48 and a pair of nuts 49 which secure the rod to the feeder deck. The upper surface of the rocker 47 is convex in shape and has a relatively large radius of curvature and bears against the weight supporting surface of the cradle 46 just as the lower surface of the rocker 44 is convex in shape and bears against the upper surface of the cradle 43. The cradle 46 is provided with an elongated opening through which the rod 41 extends so as to permit the rod 40 to swing backwardly and forwardly as the feeder deck 37 reciprocates.

The rods 41 at the forward end of the feeder deck 37 are secured to the feeder deck and the hopper in a somewhat similar manner as are the rear supporting links 41 except that the Belleville springs are disposed at the upper end of the rod rather than at the lower end thereof. This can best be seen in FIG. 5 wherein the upper end of the rod is shown carrying an identical cradle member 46a and a rocker 47a and a plurality of Belleville springs 48a. At the extreme upper end there is a pair of nuts 49a. The

lower surface of the rocker 47a is convex in shape and rocks upon the upper surface of the cradle 46a.

The lower end of each of the forward rods 41 is connected to the forward end of the feeder deck 37 as best shown in FIG. 5. Each of these rods carries at its lower end a cradle member 50, a rocker 51 and a pair of nuts 52. The upper surface of the rocker 51 is convex and rocks upon the lower surface of the cradle member 50. The cradle member 50 is provided with an elongated opening s-ufliciently long to permit the rod 41 to swing forwardly and rearwardly relative to the feeder deck 37.

It will be noted that the feeder deck 37 is indirectly supported by the frame 35 through the hopper 36. As the feeder deck 37 is caused to reciprocate, through the reversing action of the differential type cylinder 39 the weight of the load upon the feeder deck and the feeder deck itselfis supported by the rods 41. The rockers 44, 47, 47a and 5)]. rock upon their supporting surfaces rather than slipping relative thereto, so that the frictional wear therebetween is reduced to a minimum. Since there is no relative slipping movement between the weight-bearing surfaces no lubrication is necessary. The rocking action which takes place between the rockers and the cradles is of such a nature that no lubrication is required. Moreover, these weight-bearing surfaces have a self cleaning tendency in that they quickly pulverize any dirt or rock or ore which may work itself between these surfaces and the powdered material will slip outwardly and clear of the weight-bearing surfaces. The Belleville springs are utilized to absorb the severe shock to which the feeder deck 37 is subjected when the extremely heavy chunks of ore or the like are permitted to drop a distance of several feet thereupon. These Belleville springs absorb the shock and prevent any damage to the construction which would otherwise be occasioned if the feeder deck 37 were supported by rollers mounted upon axles. Through the use of this construc- 6 tion, no damage is inflicted upon the feeder deck and its reciprocating mechanism despite prolonged use under most severe conditions of heavy loading, extreme jarring,

and heavy capacities.

It should be noted that to adjust the volume of material caused to be fed by the reciprocating feeder deck 37 is only necessary to vary the volume of the hydraulic pump. It is also possible to vary the extent of reciprocating movement of the feeder deck 37 by varying the stroke of the piston, without changing the amount of material which is fed by the feeder deck, for as you shorten the stroke, the

speed of the piston at a given hydraulic volume increases.

It will be noted that the feeder deck 37 illustrated in FIG. 6 is stepped. By utilizing this type of construction, the forward movement of the material through the discharge 36a of the hopper 36 can be facilitated, for the relatively large pieces of the material such as iron ore will be more positively engaged by the feeder deck as it moves forwardly.

The third embodiment of my invention is particularly well adapted for use in situations where extremely heavy loads must be carried. As best shown in FIG. 8 the reciprocating plate feeder or feeder deck 55 is stepped and is caused to reciprocate through the use of a differential type cylinder such as is disclosed and described with respect to the construction shown in FIG. 5. This cylinder 56 is pivotally connected to the reciprocating plate feeder 55 in driving relation. The feeder deck 55 extends across the discharge 57a of a hopper 57 which in turn is supported by a frame indicated generally by the numeral 58. The particular construction shown in FIGS. 8-11, inclusive, is somewhat different from that shown in the other two embodiments of my invention but the same principle is utilized in that a pair of rocking surfaces are utilized to bear the weight of the reciprocating feeder deck and its load. This is in sharp contrast to roller type reciprocating feeders wherein it is conventional to use rollers having axles and bearings therefor which are relatively small. Neither the axles nor the hearings in such feeders can withstand the shock and weight loads experienced in heavy-duty operation. Moreover, the cost of increasing the diameters of the bearings and axles to even approach a satisfactory handling of heavy loads, along with the space which would be required for the same, makes such a modification impractical from a standpoint of either cost or usability. In the embodiment shown in FIGS. 8-11 each of the corner portions of the reciprocating feeder deck 55 is supported by a rocker member indicated generally by the numeral 59' and best shown in FIG. 10. As shown, this rocker 59 has an up per rocking surface 59a and a lower rocking surface 59b. At each side of the rocker member '59 there is a web 590 which terminates at opposite ends in a lobe 59d. The lobe 59d, when the device is assembled extends into a keeper opening 60a of a keeper member 60. One of these keeper members is bolted to the frame 5-8 as best shown in FIG. 9 at each corner of the feeder deck 55. A second such keeper 60 is bolted in inverted position as best shown in FIG. 9 to a Z-bar 61 upon which the reciprocating plate feeder 55 is welded. The other lobe 59d which is at the top of the rocker 59 extends into the keeper opening 60a of this inverted keeper 60, the two lobes 59d cooperating to prevent the rocker 59 from creeping longitudinally of the feeder deck while the latter is reciprocating.

As best shown in FIG. 1 1 each of the keeper members '60 is provided with a rail portion 6012 against which the rocker surfaces 59a or 5% as the case may be will bear. Thus as the reciprocating plate feeder is caused to move backwardly and forwardly by the cylinder 56, the rocking surfaces 59a and 5912 will rock along the rail portion 60b of its associated keeper 60 and will together bear the weight of the plate deck feeder 55 and its load. A rigid tie member 62 extends between the lower portions of each pair of the oppositely disposed rockers 59 (as shown in 7 FIG. 9) to provide rigidity for the structure. The tie member 62, as shown, is bolted at each of its ends to an attachment flange 59a of a rocker to preclude side-sway and tipping of the rockers 59.

I have found that the rockers 59 provide a very satisfactory solution in eliminating the disadvantages of using rollers to support such a feeder deck as it reciprocates. There is substantially no friction between the rocking surfaces 59a and 59b and their associated rail surface 60!). As a result there is no need for lubrication and there is very little consequential wear despite the fact that extremely heavy loads are imposed upon the feeder deck 55. The differential type cylinder provides more than adequate power to move the feeder deck 55 forwardly and backwardly and the rockers 59 provide more than adequate support for sustaining the feeder deck in elevated position. In view of the fact that there is so little friction involved, substantially less power is required to cause the feeder deck 55 to reciprocate as compared to what would be required if rollers were utilized to support the feeder deck. The big advantage, however, lies in the fact that there is no relative slipping movement between the weight-bearing surfaces and 59b and their associated rail surface $012 so that there is very little wear. By eliminating the substantial wear problem, I have eliminated substantially all of the disadvantages hereinbefore outlined as associated with roller supports for the reciprocating feeder decks. In addition, the construction shown herein is of extremely simple design and can be manufactured much more inexpensively than the type of construction wherein rollers are utilized to support the feeder deck. It should be noted also that an absolute minimum of maintenance and attention is required to the type of construction disclosed herein and that the weightbearing surfaces tend to clean themselves while they are moving relative to each other without involving substantially wear upon the surfaces.

It will, of course, be understood that various changes may be made in the form, details, arrangement and proportions of the parts with-out departing from the scope of my invention.

What is claimed is:

A withdrawal-type heavy-duty service reciprocating feed mechanism for positively feeding materials, said mechanism comprising (a) a pair of rigid transversely spaced parallel elongated frame members,

(b) a plurality of rigid transverse frame members extending between and rigidly connecting said elongated frame members at points spaced longitudinally thereof and forming therewith a rigid rectangular frame,

(c) a plurality of bracket members fixed to inner side surfaces of said elongated frame members in oppositely disposed pairs,

(d) each of said bracket members having an upwardly facing flat weight-bearing surface disposed adjacent the lower portions of said elongated frame members and extending longitudinally and inwardly thereof,

(e) each of said bracket members having a keeper opening formed therein outwardly and oppositely of said weight-bearing surface and extending therebelow,

(1) a plurality of pairs of axially spaced, oppositely disposed equally-sized rocker elements each rocker element of which has an upper and a lower opposed convex weight-bearing surface of equal radius,

(g) the lower convex weight-bearing surface of each of said rocker elements bearing upon said fiat weightbearing surface of one of said brackets in non-interengaging supported relation and rocking thereupon longitudinally of said elongated frame members,

([1) flange means carried by each of said rocker elements at its lower and upper portions and extending radially outwardly along the inner side of its supporting bracket member beyond the fiat weight-bearing surface thereof,

(1') rigid tie means extending between and rigidly connecting the lower portions of each of said oppositely disposed rocker elements and rocking therewith,

(j) a feeder deck extending between said elongated frame members and longitudinally thereof,

(k) said feeder deck having an upper rigid material supporting surface and including rigid side members extending vertically upwardly and slightly above said material supporting surface,

(I) a plurality of second bracket members fixed to outer side surfaces of said elongated frame members adjacent the upper portion thereof in transversely oppositely disposed pairs,

(m) each of said second bracket members having a downwardly facing flat weight-bearing surface extending longitudinally of said elongated frame members and rocking upon the upper convex weight-bearing surface of one of said rocker elements in noninterengaging supported relation whereby said feeder deck may be reciprocated relative to said frame,

(11) each of said second bracket members having a keeper opening formed therein inwardly and oppositely of the weight-bearing surface thereof and extending thereabove and between said weight-bearing surface and the side member of said feeder deck to which said bracket member is attached,

(0) keeper elements carried by each of said rocker elements and extending into said keeper openings of its supporting and supported bracket members, and

(p) means connected to said feeder deck for reciprocating the same.

References Cited in the file of this patent UNITED STATES PATENTS 522,779 Carstens et a1. June 10, 1894 2,214,755 Tafel Sept. 17, 1940 FOREIGN PATENTS 789,262 France Aug. 12, 1935 19,560 Great Britain Sept. 6, +1902 

